Azry Borhan

Development of Novel Low-Cost Activated Carbon for Carbon Dioxide Capture

promising solid adsorbents that can be utilized to capture CO2 due to its numerous benefits, such as inexpensive, easy for regeneration, insensitiveness towards the moisture, high CO2 adsorption capacity at ambient condition, high specific surface area, adequate pore size distribution, high mechanical strength, as well as low in energy requirement (4). Based on the benefits possessed by activated carbon, it has been widely employed in various applications, be it in gas or liquid phase. However, exploitation of the activated carbons in capturing CO2 has not been extensively evaluated. The potential of activated carbon in CO2 capture depends on few criteria such as types of activation method and nature of starting materials, which in turn affects the porosity and surface chemistry of the synthesized activated carbon (5). The chemical activation method includes the ammonia treatment and impregnation technique that have been extensively employed nowadays is uninvited as it imposes hazardous impacts towards the environment and also, results in pore blockage that may possibly lessen the adsorption capacity. Plaza et al. (2) proved that impregnation of activated carbon with amine-based compounds is not a suitable approach for CO2 capture at room temperature, as it reduces the surface area and block the microporous structure that is accountable for physical adsorption process. Specifically, the impregnated activated carbon with polyethylenimine (PEI) solvents which had BET surface area of 90 m 2 /g can only capture CO2 up to 4.9 wt%, as compared to virgin activated carbon that had total surface area of 1,762 m 2

Biosorption of Heavy Metal Ions, Oil and Grease from Industrial Waste Water by Banana Peel

The objective of this research is to study the potential of using banana peel as a biosorbent in removing heavy metal ions (Cu2+, Zn2+ and Pb2+) and oil/grease particles from industrial waste water. The study emphasizes on the parameters involved in the preparation phase of the banana peel adsorbent, such as particle sizes, activating agent, impregnation ratio, carbonization temperature and duration. Based on the findings, it shows that the adsorption capacity is correlated to the total surface area (SBET), pore volume (VT) and average pore diameter (D) of the materials. Sample A20 yields the highest percentage removal for all tested waste water pollutants, suggesting that banana peel based activated carbon can be used effectively as biosorption material.

Removal of Ni(II), Zn(II) and Pb(II) ions from single metal aqueous solution using rice husk-based activated carbon

An attempt was made to investigate the potential of rice husk-based activated carbon as an alternative low-cost adsorbent for the removal of Ni(II), Zn(II) and Pb(II) ions from single aqueous solution. Rice husk-based activated carbon was prepared via treatment of rice husk with NaOH followed by the carbonization process at 400°C for 2 hours. Three samples, i.e. raw rice husk, rice husk treated with NaOH and rice husk-based activated carbon, were analyzed for their morphological characteristics using field-emission scanning electron microscope/energy dispersive X-ray (FESEM/EDX). These samples were also analyzed for their carbon, hydrogen, nitrogen, oxygen and silica contents using CHN elemental analyzer and FESEM/EDX. The porous properties of rice husk-based activated carbon were determined by Brunauer-Emmett-Teller (BET) surface area analyzer, and its surface area and pore volume were 255 m2/g and 0.17 cm2/g, respectively. The adsorption studies for the removal of Ni(II), Zn(II) and Pb(II) ions from sin...

Novel Low-Cost Activated Carbon from Coconut Shell and its Adsorptive Characteristics for Carbon Dioxide

The objective of this research is to synthesize the microporous activated carbon and test its applicability for CO2 gas capture. In this study, coconut shell-based and commercial activated carbon is used as the solid adsorbent. Based on the findings, it shows that the gas adsorption capacity is correlated to the total surface area of the materials. In addition, reduction in the adsorption capacity with respect to temperature proves that the physisorption process is dominant. Higher carbon dioxide (CO2) adsorption capacity in comparison to nitrogen (N2) capacity contributes to higher CO2/N2 selectivity, and confirms its applicability in the post-combustion process. Utilization of abundance agricultural wastes and one-step physical activation process is attractive as it promotes a cleaner pathway for activated carbon production, and simultaneously, reduces the total operating cost.

Development of activated carbon derived from banana peel for CO2 removal

This research work highlights on the constraints involved in the preparation of the banana peel bio-sorbent, such as impregnation ratio, activation temperature and period of activation for reducing carbon dioxide (CO2) in the atmosphere. Micromeritics ASAP 2020 and Field Emission Scanning Electron Microscope (FESEM) were used in identifying the best sample preparation method with the largest surface area which directly contributes to the effectiveness of adsorbent in removing CO2. Sample A10 was identified to yield activated carbon with the largest surface area (260.3841 m2/g), total pore volume (0.01638 cm3/g) and pore diameter (0.2508 nm). Through nitrogen adsorption-desorption isotherm analysis, the existence of sub-micropores was proven when a combination of Type-I and Type-II isotherms were exhibited by the activated carbon produced. The results from the final adsorption test found that the material synthesized from the above mentioned parameter is capable of removing up to 1.65% wt of CO2 through ad...

Adsorptive Removal of Ni2+ from Aqueous Solution onto Rice Husk-Based Activated Carbon

The potential of rice husk-based activated carbon (RHAC) as an alternative low-cost adsorbent for the removal of Ni2+ from aqueous solution was studied. RHAC was prepared via chemical treatment using NaOH followed by the carbonization process. The textural properties of rice husk-based activated carbon, i.e. surface area (253 m2/g) and pore volume (0.17 cm2/g), were determined by N2 adsorption. The adsorption studies to remove Ni2+ from aqueous solution using RHAC were carried out at a fixed initial concentration of Ni2+ (150 ppm) with varying RHAC as a function of contact time at room temperature. The concentration of Ni2+ was determined by atomic absorption spectrophotometer (AAS). The maximum removal of Ni2+ was increased from 40% to 89% when the amount of RHAC was increased from 0.1 g to 0.5 g. The isotherm and kinetic analyses showed that equilibrium data of adsorption studies fitted well Langmuir, Freundlich and second order kinetic models.

Characterization of Activated Carbon from Wood Sawdust Prepared via Chemical Activation Using Potassium Hydroxide

The preparation of activated carbon from wood-based industrys residue is one of the most environmental friendly solutions of transforming negative-valued wastes to valuable materials. Wood sawdust was first chemically activated using potassium hydroxide, KOH and characterized by nitrogen adsorption-desorption isotherms measured in Micrometrices ASAP 2020 and Field Emission Scanning Electron Microscope (FESEM). By manipulating three different parameters, the optimal activation conditions were found at temperature of 500°C, activation time of 60 min and impregnation ratio of 1:3. Results showed that the BET surface area, total pore volume and diameter of activated carbon were 1876.16 m2 g-1, 0.88 cm3 g-1 and 6.93 nm, respectively. Nitrogen adsorption desorption isotherm analysis proved the existence of mesopores in activated carbon produced, suggesting that it can be effectively used as an adsorption material.